Nanofiber scaffolds for biological structures

Abstract

A system for manufacturing an artificial construct suitable for transplantation into a biological organism that includes a two or three three-dimensional preform that is based on the actual two or three-dimensional structure of a native mammalian tissue; and an electrospinning apparatus, wherein the electrospinning apparatus is operative to deposit at least one layer of polymer fibers on the preform to form a polymer scaffold, and wherein the orientation of the fibers in the scaffold relative to one another is substantially parallel.

What is claimed: 
     
       1. A synthetic construct consisting of:
 a single layer of electrospun polymer fibers, wherein at least about 75% of the fibers have a fiber angle within about 10° of parallel; 
 wherein the single layer has a shape of a patch and a thickness from about 0.2 mm to about 3 mm. 
 
     
     
       2. The synthetic construct of  claim 1 , wherein the electrospun polymer fibers comprise a natural polymer selected from the group consisting of collagen, gelatin, fibronectin, hyaluronic acid, and combinations thereof. 
     
     
       3. The synthetic construct of  claim 1 , wherein about 92% of the electrospun polymer fibers have a fiber angle within about10° of parallel. 
     
     
       4. The synthetic construct of  claim 1 , wherein the electrospun polymer fibers comprise a polymer selected from the group consisting of polyethylene terephthalate, polycaprolactone, polylactic acid, polyglycolic acid, polyetherketoneketone, polyurethane, polycarbonate, polyamide, and combinations thereof. 
     
     
       5. A system comprising:
 a rotatable preform based on a structure of a native mammalian tissue; and 
 an electrospinning apparatus comprising at least one anti-static bar; 
 wherein the at least one anti-static bar is positioned from about 0.5 inches to about 3 inches away from the rotatable preform. 
 
     
     
       6. The system of  claim 5 , wherein the electrospinning apparatus includes a fiberization tip. 
     
     
       7. A method of making a synthetic construct, the method comprising:
 creating an electronic field of about 1-40 kV proximate to a fiberization tip; 
 positioning a first ground within a preform; 
 positioning at least one anti-static device from about 0.5 inches to about 3 inches away from the preform; 
 rotating the preform in a rotation direction at a rotation rate; 
 extruding from the fiberization tip at a flow rate a polymer solution comprising a polymer and a solvent; and 
 depositing by electrospinning a plurality of polymer fibers on the preform, wherein at least about 75 % of the electrospun polymer fibers deposited have a fiber angle within about 10° from the rotation direction of the preform. 
 
     
     
       8. The method of  claim 7 , wherein the solvent is selected from the group consisting of acetone, dimethylformamide, trifluoroactic acid, hexafluoroisopropanol, acetic acid, dim ethylacetamine, chloroform, dichloromethane, water, ionic compounds, and combinations thereof. 
     
     
       9. The method of  claim 7 , wherein the at least one anti-static device is an anti-static bar. 
     
     
       10. The method of  claim 7 , wherein the rotation rate is about 15.7 meters per second. 
     
     
       11. The method of  claim 7 , wherein the percentage of the electrospun polymer fibers having a fiber angle within about 10 degrees of the rotation direction of the preform is selected from the group consisting of about 75%, about 91%, about 92%, and about 98%. 
     
     
       12. The method of  claim 7 , wherein the preform further comprises a second ground. 
     
     
       13. The method of  claim 12 , wherein the depositing by electrospinning further comprises alternating a ground between the first ground and the second ground. 
     
     
       14. The method of  claim 7 , wherein the flow rate is about 1.0 ml/h. 
     
     
       15. The method of  claim 7 , wherein the polymer is selected from the group consisting of polyethylene terephthalate, silicone, polyurethane, polycarbonate, polyether ketone, polycaprolactone, polylactic acid, polyglycolic acid, and combinations thereof.